Mercurial > dropbear
diff cli-authpubkey.c @ 391:00fcf5045160
propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head c1db4398d56c56c6d06ae1e20c1e0d04dbb598ed)
to branch 'au.asn.ucc.matt.dropbear' (head d26d5eb2837f46b56a33fb0e7573aa0201abd4d5)
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Thu, 11 Jan 2007 04:29:08 +0000 |
parents | 454a34b2dfd1 |
children | b895f91c2ee6 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cli-authpubkey.c Thu Jan 11 04:29:08 2007 +0000 @@ -0,0 +1,188 @@ +/* + * Dropbear SSH + * + * Copyright (c) 2002,2003 Matt Johnston + * Copyright (c) 2004 by Mihnea Stoenescu + * All rights reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. */ + +#include "includes.h" +#include "buffer.h" +#include "dbutil.h" +#include "session.h" +#include "ssh.h" +#include "runopts.h" +#include "auth.h" + +#ifdef ENABLE_CLI_PUBKEY_AUTH +static void send_msg_userauth_pubkey(sign_key *key, int type, int realsign); + +/* Called when we receive a SSH_MSG_USERAUTH_FAILURE for a pubkey request. + * We use it to remove the key we tried from the list */ +void cli_pubkeyfail() { + + struct SignKeyList *keyitem; + struct SignKeyList **previtem; + + TRACE(("enter cli_pubkeyfail")) + previtem = &cli_opts.privkeys; + + /* Find the key we failed with, and remove it */ + for (keyitem = cli_opts.privkeys; keyitem != NULL; keyitem = keyitem->next) { + if (keyitem == cli_ses.lastprivkey) { + *previtem = keyitem->next; + } + previtem = &keyitem; + } + + sign_key_free(cli_ses.lastprivkey->key); /* It won't be used again */ + m_free(cli_ses.lastprivkey); + + TRACE(("leave cli_pubkeyfail")) +} + +void recv_msg_userauth_pk_ok() { + + struct SignKeyList *keyitem; + buffer* keybuf; + char* algotype = NULL; + unsigned int algolen; + int keytype; + unsigned int remotelen; + + TRACE(("enter recv_msg_userauth_pk_ok")) + + algotype = buf_getstring(ses.payload, &algolen); + keytype = signkey_type_from_name(algotype, algolen); + TRACE(("recv_msg_userauth_pk_ok: type %d", keytype)) + m_free(algotype); + + keybuf = buf_new(MAX_PUBKEY_SIZE); + + remotelen = buf_getint(ses.payload); + + /* Iterate through our keys, find which one it was that matched, and + * send a real request with that key */ + for (keyitem = cli_opts.privkeys; keyitem != NULL; keyitem = keyitem->next) { + + if (keyitem->type != keytype) { + /* Types differed */ + TRACE(("types differed")) + continue; + } + + /* Now we compare the contents of the key */ + keybuf->pos = keybuf->len = 0; + buf_put_pub_key(keybuf, keyitem->key, keytype); + buf_setpos(keybuf, 0); + buf_incrpos(keybuf, 4); /* first int is the length of the remainder (ie + remotelen) which has already been taken from + the remote buffer */ + + + if (keybuf->len-4 != remotelen) { + TRACE(("lengths differed: localh %d remote %d", keybuf->len, remotelen)) + /* Lengths differed */ + continue; + } + if (memcmp(buf_getptr(keybuf, remotelen), + buf_getptr(ses.payload, remotelen), remotelen) != 0) { + /* Data didn't match this key */ + TRACE(("data differed")) + continue; + } + + /* Success */ + break; + } + buf_free(keybuf); + + if (keyitem != NULL) { + TRACE(("matching key")) + /* XXX TODO: if it's an encrypted key, here we ask for their + * password */ + send_msg_userauth_pubkey(keyitem->key, keytype, 1); + } else { + TRACE(("That was whacky. We got told that a key was valid, but it didn't match our list. Sounds like dodgy code on Dropbear's part")) + } + + TRACE(("leave recv_msg_userauth_pk_ok")) +} + +/* TODO: make it take an agent reference to use as well */ +static void send_msg_userauth_pubkey(sign_key *key, int type, int realsign) { + + const char *algoname = NULL; + int algolen; + buffer* sigbuf = NULL; + + TRACE(("enter send_msg_userauth_pubkey")) + CHECKCLEARTOWRITE(); + + buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_REQUEST); + + buf_putstring(ses.writepayload, cli_opts.username, + strlen(cli_opts.username)); + + buf_putstring(ses.writepayload, SSH_SERVICE_CONNECTION, + SSH_SERVICE_CONNECTION_LEN); + + buf_putstring(ses.writepayload, AUTH_METHOD_PUBKEY, + AUTH_METHOD_PUBKEY_LEN); + + buf_putbyte(ses.writepayload, realsign); + + algoname = signkey_name_from_type(type, &algolen); + + buf_putstring(ses.writepayload, algoname, algolen); + buf_put_pub_key(ses.writepayload, key, type); + + if (realsign) { + TRACE(("realsign")) + /* We put the signature as well - this contains string(session id), then + * the contents of the write payload to this point */ + sigbuf = buf_new(4 + SHA1_HASH_SIZE + ses.writepayload->len); + buf_putstring(sigbuf, ses.session_id, SHA1_HASH_SIZE); + buf_putbytes(sigbuf, ses.writepayload->data, ses.writepayload->len); + buf_put_sign(ses.writepayload, key, type, sigbuf->data, sigbuf->len); + buf_free(sigbuf); /* Nothing confidential in the buffer */ + } + + encrypt_packet(); + TRACE(("leave send_msg_userauth_pubkey")) +} + +int cli_auth_pubkey() { + + TRACE(("enter cli_auth_pubkey")) + + if (cli_opts.privkeys != NULL) { + /* Send a trial request */ + send_msg_userauth_pubkey(cli_opts.privkeys->key, + cli_opts.privkeys->type, 0); + cli_ses.lastprivkey = cli_opts.privkeys; + TRACE(("leave cli_auth_pubkey-success")) + return 1; + } else { + TRACE(("leave cli_auth_pubkey-failure")) + return 0; + } +} +#endif /* Pubkey auth */